This invention relates to a channel section for a scraper-chain conveyor, and to a scraper-chain conveyor constituted by a plurality of channel sections joined together end-to-end.
Known scraper-chain conveyors, which are used primarily in underground mine workings, are constituted by a series of channel sections (or pans), which are connected together in an end-to-end relationship. The channel sections are joined together (for example by means of toggle bolts) in such a manner as to resist tensile forces which tend to draw in the ends of the channel sections apart; whilst permitting some angular mobility, in the vertical and horizontal directions, between the channel section ends. This enables the conveyor to adapt itself to uneven areas of the floor of a mine working, as well as permitting the conveyor to be advanced in sections. Typically, the channel sections have side walls constituted by sections having a generally E- or sigma-shaped profile, a floor plate being welded between the side walls. To prevent the formation of gaps between the floor plates at the channel section interfaces as adjacent channel sections are subjected to relative angling during conveyor advance, through which gaps fine material could pass from the upper run into the lower run, the floor plates are so formed that they overlap at the interfaces. This results, in practice, in the conveyor being able to move material only in one direction (if the scraper assembly of the conveyor was circulated in the opposite direction, the scrapers would have to pass over the overlapping floor plate joints, and this would lead to heavy impact loading and to excessive noise, both of which are undesirable).
It is also known to form the floor plates of the chanel sections as double floor plates which overlap at the interfaces. Alternatively, intermediate plates may be provided to bridge the joints at the interfaces, the intermediate plates being inserted between the double floor plates which are, accordingly, spaced apart (see DE-AS No. 1 275 023 and DE-PS No. 902 236). It is also known to form each of the channel sections from a conveyor tray and a return tray connected thereto. In this case, the conveyor tray can constitute a replaceable wear member (see DE-AS No. 2 254 129, DE-AS No. 1 097 988, DE-PS No. 935 779, DE-AS No. 2 210 897 and DE-OS No. 3 109 329). Unfortunately, all of these arrangements are complicated and costly constructions.
The aim of the invention is to provide a scraper-chain conveyor, and a channel section therefor, which can be made by simple manufacturing methods, which is such that the gap between the floor plates of adjacent channel sections can be sealed off in a reliable manner without the use of special intermediate members, and which permits conveying to take place in both directions.